P projection is a stated aim of our armed forces. It is the distillation of much of what our armed services exist to do. We vaunt our ability to intervene powerfully almost anywhere we choose to and win once we are there. Power on that scale is quintessentially American. Its roots, however, can be found in Antiquity. What, after all, were the Greeks doing at the gates of Troy but projecting power? Yet before the Industrial Revolution power could only be projected on a small scale. Afterwards power projection on a large scale became possible and flowered in response to the demands of Western imperialism. As Aaron Friedberg noted in an earlier book, from a military perspective “the most important product (of the Industrial Revolution) was a marked improvement in the ability of European states to project and maintain military power far from their own frontiers.”1 The United States is the inheritor of that experience.